The hot air which is emitted during cooking includes substances which have emanated from the foodstuffs themselves, as well as others derived from fats and oils used in the cooking process. Some of these are responsible for typical cooking smells whilst others may appear as smoke. A portion of this smoke may later condense to form greasy deposits of particulate matter in the oven itself and surrounding areas.
In a busy commercial kitchen it is often necessary to keep cooking fumes under control, for the following reasons:
To make the kitchen a more pleasant working environment
To improve the air quality in the dining area, if the building is open-plan
To prevent a build-up of greasy deposits which may constitute a health or fire risk
To reduce nuisance smells outside the building
To prevent flavour transfer from one type of foodstuff to another
To enable a building without an extraction system to be used as a kitchen
In a domestic situation cooking smells are generally more acceptable, however fumes from pyrolytic self-cleaning ovens can be very unpleasant and even dangerous.